Define Polycarbonate glue...

[VKP]

If a bottle of epoxy says that it can be used for "plastics," will it pass inspection as a polycarbonate glue?

[pfreivald]

CD really isn't the place to ask...

[Joe Ross]

Originally Posted by pfreivald

CD really isn't the place to ask...

Is there a place to ask right now? Q/A is closed, and this doesn't seem like type of question to tweet the refs about.

[Teched3]

Originally Posted by Brandtlamonte

Could someone please use references to find whether Super glue, Epoxy, etc. Count as polycarbonate glues? I've tried but failed =/

If you go to the Loctite website, you can browse through their adhesives, and you will find what you are looking for in their descriptions of what materials they will bond. Search for the data sheet. Loctite makes many more products than "thread locker" materials. The rules do not state "marketed as" as was done with the limit switch. One formulation that I researched is called "ultra gel control". this may be suitable for your needs.

[pfreivald]

Originally Posted by Joe Ross

Is there a place to ask right now? Q/A is closed, and this doesn't seem like type of question to tweet the refs about.

I hear ya, but it seems a little late...

[Teched3]

Originally Posted by pfreivald

I hear ya, but it seems a little late...

Print out a copy of the data sheet and show it to the inspectors when you go for inspection. You should be OK. Most of these products should be used in a well ventilated area, so don't use in the pit area. Outside application only - fumes fire hazard, etc concerns.

This is directly from the GDC:

01-31-2011, 03:40 PM
GDC
Game Design Committee
$@#
Join Date: Jan 2006
Posts: 2,782
Re: Polycarbonate Glue
Any glue that is marketed as specifically for bonding polycarbonate is allowed per R92-G.

I stand corrected on my original post related to limit switches.

[Retired Starman]

Questions like, "What is polycarbonate glue?" somewhat amuse me. Maybe it's because I have had years of experience doing fabrication while kids are new to the process. So let me explain. This goes for items in the minibot list, like the allowable cements and "household light switches".

Quite specifically, if you go to a commercial supplier of sheet plastic products, on the shelf by the order counter, you will find bottles of glues called "Polycarbonate Cement" and "Acrylic Cement". Such products are what fulfill the definition as listed in the allowable parts list, just as PVC cement is what comes in the can called PVC Cement that you get in the plumbing department of the local hardware or building products store. It's that simple.

This isn't really rocket science, guys. Stop trying to make it difficult. Stop trying to run around looking for loopholes and work within the Game Design Committee limitations on construction. In the real world, those limitations are called "specifications" and they are what the customer pays you to use when you design the project you are selling them.

As a robot inspector, I'll accept any glue which specifically says in its literature that a recommended use is to glue polycarbonate, but if it isn't real polycarbonate cement, expect a big eye roll! And expect to show me that product documentation.

Dr. Bob

[Jaxom]

Originally Posted by Retired Starman

This isn't really rocket science, guys. Stop trying to make it difficult. Stop trying to run around looking for loopholes and work within the Game Design Committee limitations on construction. In the real world, those limitations are called "specifications" and they are what the customer pays you to use when you design the project you are selling them.

As a robot inspector, I'll accept any glue which specifically says in its literature that a recommended use is to glue polycarbonate, but if it isn't real polycarbonate cement, expect a big eye roll! And expect to show me that product documentation.
Dr. Bob

Thank you.

[Tristan Lall]

Originally Posted by Retired Starman

As a robot inspector, I'll accept any glue which specifically says in its literature that a recommended use is to glue polycarbonate, but if it isn't real polycarbonate cement, expect a big eye roll! And expect to show me that product documentation.

There's at least one other special case that merits consideration: glue that is polycarbonate. Granted, that's pretty unlikely, but I know of at least a few adhesives that contain small beads for setting the bond gap. It's not inconceivable that polycarbonate could be an ingredient, making it a "polycarbonate glue". I don't think that's what the GDC intended, and I wouldn't advise trying that for new designs...but in the unlikely event that a team already used this substance, they might as well bring a datasheet listing the ingredients, and see what the inspectors think. (But be prepared to change it....)

I wonder if the GDC intended the rule to refer only to ordinary solvent-based cements (as described above), or if they considered more exotic adhesives? I also wonder whether, on balance, it would have been more useful to allow any glue used only to join polycarbonate pieces. (Wasn't sticking plastic together the core intent? I say that, because solvent cements don't really work on anything but certain plastics, so it's reasonably likely that they didn't expect teams to use the glue to attach plastic to the rest of the minibot. Of course UV-curing multipurpose adhesives designed for polycarbonate exist, and would work for that purpose.)

And as for datasheets, Loctite's are excellent; search for "Loctite [number] TDS", and you'll get a lot of good information on best practices.

For reference regarding what works (but not necessarily what's legal), this Handbook of Plastics Joining looks helpful. See table 27.9 on page 305 for some information on polycarbonate and various adhesives.